Centrifugal fan and pump.



G. M; GAPELL.

OENTBIFUGAL FAN AND PUMP.

'APPLICATION FILED JULY 31,11909.

` Patented 1nmy2',1911.`

Pronostici-.4

ENGLANXJ.

Specification of Letters etent.

` Application. met muy ai,

To all whom it may concern:

Be it known that l. (leonor: Minnie Cn- PELL, o. subject of the King ot Greet Briten),

residing et Passenhsm Rectory, near Stony Stratford, in the county ci? Northenipton, England, have invented new und useitul 11nprovements 1n Centrifugal Fens und. Pumps,

of which the follow-ing is n speeificntion.

gctionmerely.

In the operation of funs and centrifugal umps of normal construction, o. loss oi' et ect is nearly always encountered which is due to the return flow, toward the center ot' the wheel et the back of u vene, of sonic ot the fluid delivered through theouter periphery of the wheel from the front fecen of the vane. Such un action muy be regarded as a spilling of seineA of the contents ot the vane-buckets which are employed in conveying the uid from u region oi relatively low pressure to one et higher preniure1 this re turn How or spilling action being due to the well-known tendency of u moving surface to create, :it the buck thereof, a pressure'which is less then that 'ot the surrounding fluid tlirough which the surface is trav cling which action Indy be referred to shortly 4es cevitutionaction l..

i By means ot e teilfblide secured to the back of a. vene ond diverging therefrom in a radially outward direction et. :i rute greaterthnn that due to the inereincrease of radius, Athe tendency for duid to return along the beck of the vane willV be counteracted and by sepa-rating the toil-binde troni the venefhnd providing between the il'iner edge of the teibblede und the buck of the vane a liberal passage for the dow of Huid between them, cuvitetion Inotion, which previously was `a cause of loss of effectj will be converted into'ztpotent lcause ot' eugmentation of effect." The flow of fluid through N.the divergingrspace between the tail-blade and the Yback of Ithe vene, induced by envitetion action und rendered operative by the above described modified coi'istruction, is en tirely additional to that due to centrifugal Hoving by such u ynew methodjof inspiration induced fluid to en` .terffthe inclosed space at the beck of the vene,A such additional ludlwill become, by the impelling eect ofthe rear or teil-blade, subject to the head due to the whirling vmotion of the. wheel,` like the fluid which is drivenin `front ofthe vene, and the *conse-r quentfevacuatlon vof one mass of such addi- 'otented'lWIuy 2, 1911.

1909. Serial No. 510,550.

tionally inspired fluid will necessitate its pince being teken by another uniss and so on continuously, the inspiration of a' fresh ini-(iss due to the centrifugal evacuation of u preceding` mass superposing itself on inspiration due to cuvitution, resultingin a. considerably augmented output of fluid :troni the wheel.

The object of the present invention is in the first place to enhance the above de scribed effect und, second to show how the effect con be derived by u n'iore simple, and reliable construction than .that previously described. f

According to the' present invention I arrange to delire/noir to the space between the venewrnd u following divergent tailblude from the 'front of the vene "through it port-hole formed in the vane itself or e port.- hole formed in the tail-blade, or by portholes formed in the tail-blade as Well as in the'vene. Onesor more such portholes muy be formed in each vene or the principal venes may be 'formed with two port-holes und scoop-shaped extensions into the air inlenL circle of the wheel muy be added to such principal venes1 there being interposed secondaryvunes formed with a single port-4 hole in the vane itself, in the tail-blade thereof or in both the vane and tail-blade, scoop-shaped extensions being omitted from these secondary' venes.

The details oit the construction may be varied as will be described-with reference to the accompanying drawing.

In this drawing' c-Figure l. is e transverse section 'et' u single-ported Winer-Fig 2 bcing an isometric View of the sume. Fig. 3 is en isometric view of u single-ported vene varied in some details. lFig'. 4 is a transverse sectionmf e double-ported vane z-Fig 5 being an isometric view of the same. Fig.v 6 is a." transverse section of a. single-ported vene .combined with a single-ported tail` blade, Figs. 7 and 8 being isometric front and buck views respectively of such a vane. Fig. 9 is a. yrepresentative exemple of an as sembluge of single and double-ported venes' onewheel.

- In Figs. 1 and 2 is shown `e vane in which a single port-hole is formed of'less thunthe full widthof the vane;` bycuttingthree sides of a rectangular orifice in the vane plate a and bending the portion b, thus partiallyy severed, about the uncut edge of the orice,I

' the vane-plate a into the space at the back of the vane and in front of a tail-blade c which is secured to the inner edge d of the port-hole and extends, asshown inv Fig. l,

as far as the outer periphery of the Wheel with a gradually increasing ratesof divergence. The spaces behind the side portions" of the vane, indicated by a1 a1 in Fig. 2, will be supplied with fluid by a lateral deviation of a portion of that which enters the porthole and the fluid which flows over the front of the side portions al a1 will avoid interference by the deflectingy plate b. i

In Fig'. 3 `gusset-shaped side-plates e e are provided to more completely separate the streams of fluid which flow overY the front face of the vanefrom that deflected by Z) to the back of the vane. The construction of Fig. 3 still further differs from that of Figs. 1-2 in respect to the fact that the tail'blade c-diverges from the back of the lvane at a rate. which first gradually increases and then gradually decreases so that the tail-blade is concave to the baci; of the vane. 4 the outer periphery of the Wheel, the tailbladc c may stop short thereof.

Figs. 4 and 5 show double-ported Yanes, the outer port having a defiecting plate b1 leading forward and inward from the outei edge of the portl1ole, and a tail-blade c" leading backward and outward from the iiiner edge of the port-hole. A corresponding detlecting plate b2 and a tail-blade c2 are -fitfed to the outer and inner edges respectively ol" the inner port-hole. lVith such a construction there will be a duplex inspiration effect, for not only will the tendency to cavitation at theback ot the outer porfion of the main-vane be utilized to augment vthe flow of fluid. through the Wheel by the combined operation of the outer vport-hole and the tail-blade c1 thereof, but also the tendency to cause cavitation at the back of the tail-blade cl will be requisitioned to induce still more fluid 'to flow tlirongl'i the Wheel by the combined' effect of the inner port-hole and the tail-blade o2 secured to its inner edge'. The principle of action above described mayy be utilized stillfurther by the employment of more than two porteholes in each vane.

In Fig. G is shown a vanein which the port-hole construction is applied to the tailblade c as Well as to the vane itself, Fig. T v

showing the port-hole in the Avane and Fig. 8 the port-hole in the tail-blade. In the drawing the port-hole in the vane is shown,

Instead of extending as far of less width than the port-holein the tailblade, the fluid deflected by the plate b being in this arrangement intended to assist in e'ntraining other fluid Lnrough the wider port-hole formed in the tail-blade, the combination enhancing the before described inspiration effect. The port-hole construction of tail-blade whereby fluid is admitted'to theI diverging space provided'between the Vane and tail-blade possesses the advantage that the partial vacuum tended to be continually maintained by centrifugal action Within the divergiiig space between the sides marked c1 c1 (Fig. 8) of the tail-blade and the vane has a flow-inducing effect on the fluid. Accordingly the port-liole construe* tion of tail-blade may be adopted with ad ,vantage even Without a port-hole in the vane itself.

Fig. 9 shows an assemblage of double... ported prlncipal vanes A1 A2 with an interposed single-ported secondary vane E provided with a single port and a tail-blade which does not extend to the outer periphery of the wheel. The principal venes A1 A2 l. In a centrifugal fan or pump-Wheel, a `vane formed w1th a port-hole therein and a tail-blade at the back of the vane the surface' of which is so shaped and situated as to diverge from the back surface of the vane at a rate which is greater than that due to mere increase 0f radius.

2. In a centrifugal fan or pump-Wheel, a yane formed with a port-hole therein and a tail-blade at the hack ot the vane the surface of which is so shaped and situated to di- \'e1ge from the hachv surface of the 'vane at a. rate which is greater than that due to .more increase ot' radius and which is so situated 'and vdirected as to guide the fluid whichy proximity with the inner edge ci the port! hole, the tail-blade being so verge from the back of the van` 4. In a centrifugal fan or pump-wheel, a vane formed with a port-hole therein and a tailblade, the inner edge of Which'is se- 'cured to the inner edge of the port-hole, the

tail-,blade being so shaped as to diverge from lthe back of the vane.

.75. In `a centrifugal fan orI pump-Wheel, a. vane formed with a port-hole therein and a tail-blade, the inner edge of which is in close proximity with the inner edge of the porthole, the taihblade being so shaped as to dif rerge from the back of the Vane and extend toa` greater radius than that of the outer edger of the porthole. t 6. In a centrifugal fan or pump-Wheel, a vane forined'with a port-hole therein, a tailblade extending backward from the inner edge otl the portdiole in a direction diverging from the Vane to a radins greater than that of the outer edge of the port-hole, and a detleetiiig plate leading from the outer edge of the port-hole in a direction forward from the Vane and toward the axis of the Wheel.

T. In a centrifugal fan or pump-Wheel, a Vane formed with a port-hole therein, a tailblade extending backward/from the inner edge of theport-hole in a direction diverging from the vane, a defleeting plate leading from the outer edge of the port-hole in a direction forward from the Vane and-toward the axis of the wheel and gusset. side-plates leadingI from opposite edges of the detleeting plate to the forwardl surface of the vane.

8. In a centrifugal fan or pump-wheel, a vane formed With a port-hole therein and a tail-blade at the back of the vane the surface of which is Aso shaped and situated as to diverge from the back surface of the vane at a rate which is greater than that due to mere increase of radius, the said tail-blade being concave to the hack surface of the Vane.

9. Iii a centrifugal fan or pump-wheel, a vane formed with a plurality ot' port-holes and for each port-hole a tail-blade leading in a fdivergent direction backward. from the `rane from the inner edge of tlie-port-hole and extending to a radius greater than that of the outer edge of the port-hole.

10. A centrifugal fan or pump-Wheel,

comprising a plurality of vanes formed With' port-holes therein and diverging tail-'blades leading rearward from the inner edges' of the port-holes and seoop-shapedadditionsto suoli vanes extending into the airl inlet cir` cle of the wheel.

11. A 4centrifugal fan or pump"""'wheel,

comprising a plurality of seoop-provided l Yanes anda plurality of interposed Vanes without scoops, eaeh Vane being formed with a porthole therein fittedwith akbaelm'ardlyv diverglng tail-blade extending g from the inner edge ofthe port-hole to a radial distance not less than the radius of the outer edge of the said port-hole.

l2. In a centrifugalV fan or pump-Wheel, a combination comprising a vane and a tailblade at the back of the Vane, the surface of which is so shaped and situated as to diverge from the back surface of the vane at a rate which is greater than that due to mere increase of radius, the tail-blade being foi-ined with a port-hole therein.

13, In a centrifugal fan or pump-wheel a combination comprising a vane anda tail blade secured thereto, the vane and the tailblade 4having each a port-hole formed therein.

14. In a centrifugal fan or pump-Wheel, a combination oinprising a vane formed with a port-hole and a tail-blade formed With a port-hole and secured to said vane, the width ot' the port-hole in said vane being less than the width of the port-hole in said tail-blade.

In testimony whereof I have signed my naine to this specification in the presence of two subscribing witnesses.

GEORGE MARIE CAPELL. Yitnesses HENRY lli-Tann Wixoiionis, H. D. JAMESON. 

